LARVAL FORMS OF COLEOPTERA 



Mala simple, or division either indicated by distal notch or 

 present with lobelike galea ; mandible -with or -without a 

 molar part but without a longitudinal series of hairs at the 

 base. (Hypopharynx membranous or with a sclerome) 18 



13. Either with exposed gills below the entire abdomen, or with 



movable operculum usually covering retractile gills at the 

 end of the body, or with maniillaeform appendices from the 

 tenth abdominal segment ;^^ mandible never perforate or 

 deeply cleft. (Usually with one large ocellus on each side 

 and without true urogomphi). 



Drijopoidea (p. 44) 

 Gills or anal appendices usually absent ; in larvae where pres- 

 ent, mandibles either perforate or deeplv cleft longitudi- 

 nally ' 14 



14. Ninth abdominal segment operculate, vertical, and terminal. 



( Spiracles bif orous ; body cylindrical and strongly chiti- 

 nized; mental-submental area distinctly triangular.) 



Elaieroidea-Ehipicerklae (p. 49) 

 Ninth abdominal segment otherwise 15 



15. Spiracles cribriform ; tenth abdominal segment terminal ; pro- 



thorax large and more or less depressed, usually covered with 

 a plate both dorsally and ventrally. 



Elateroidea-Bupresiklae (p. 49) 

 Spiracles, tenth abdominal segment, and prothorax other- 

 wise 16 



16. Labrum present Cleroidea (p. 55) 



Labrum absent or included in nasale. (In Throscidae and 



Melasidae, head capsule or mouthparts very much reduced 

 or abnormal ; prothorax provided ventrally, or both dorsally 

 and ventrally, with pairs of rod-shaped scleromes (pi. 

 81)) , 17 



17. Frontal sutures present, except in Throscidae and ]\Ielasidae in 



which head capsule and mouthparts are reduced or very 

 much specialized. (Mandible of the biting labidomorphic 

 type ; head capsule with deep subf acial sinus for reception of 



ventral mouthparts) Elateroidea proper (p. 50'"^^) 



Frontal sutures absent, except in Brachypsectridae and Ijam- 

 pyridae ; both with piercing mandibles. (Mandible of the 

 biting labidomorphic type, or of the subulate type adapted 

 for piercing and sucking ; subf acial sinus present or absent^^) 



Cantharoidea (p. 46) 



^^ Eurypogon, a type intermediate between the Dryopoidea and 

 the elateroid familv Cebrionidae, has no gills or appendices (pi. 

 69). 



^*^ Sometimes with j)seudocribriform spirales (pi. 78). 



13 



